Safety stair tread



E. VAN DER PYL SAFETY STAIR TREAD Filed Dec. 17. 192] 4 .4 WITNESSES INVENTOR m 1 .3 I

@WARD VAN DER PY L, 0F WORCESTER, MASSACHUSETTS, ASSIGNOR TO NORTON COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

SAFETY STAIR TREAD.

Application filed December 17, 1921. Serial No. 523,179.

To all whom it may concern:

Be it known that I, EDWARD VAN DER P L,

a citizen of the United States of America, re-.

siding at Worcester, in the county of 'Worcester and State of Massachusetts, have invented certain new and useful Improvements in Safety Stair Treads, of which the followinis a full, clear, and exact specification.

l invention relates to safety stair treads and more particularly to a stair tread having an anti-slipping tile forming the nosing thereof. 7 Among the numerous materials which have been employed as a flooring or a safety stair tread, it has been found that tiles composed of ceramic bonded abrasive grains, such as described in the patent to Dodge No. 1,377,960, prove most satisfactory in attaining this result and in withstanding the wear of such service.

It is, however, dificult in some constructions to by such tiles according to the previous methods without a considerable expenditure of time and labor. They have a rather brittle structure and must therefore be thoroughly supported upon an even foundation. In building a new tread, the tiles are preferably supported on a setting of cement; but in repairing old stairs, such as those made of wood, the use of cement would ordinarily r uire tearing down the old construction an building it anew. Furthermore, it is often undesirable to set the tiles permanently on a base, such as cement, in which case a removable fastener should be provided to hold the tiles in place. Such a fastener must, however, satisfy the requirements of holding the tiles in such manner that they cannot be broken or loosened from their settings by normal usage and of leaving the tread surface and particularly the nose of the tile fully exposed for gripping the pedestrian foot gear.

It is accordingly an object of my invention to provide a new type of anti-slipping stair tread in which ceramic bonded abrasive tiles shall be securely fastened to the stair but which will not present a slippery surface in the nose portion of the stair or where most exposed to the trafic, which will hold the tiles securely inplace and yet prevent their being cracked by undue strains and which will peit of a tile being readily removed if this should become necessary. Further obapparent in the follow- 'tile shown in Fig. 1.

In accordance with my invention, I provide a safety stair tread by utilizing the ordinary stair constructions, such as wooden or iron stairs, and render the same safe for pedestrians by fastening a row of tiles of ceramic bonded abrasive grains on the front of the tread base. As one embodiment of my invention, I have shown in the drawings how the tiles 10 may be applied to a wooden stair of the usual type. As there shown, the wooden stair comprises a tread base 11 and riser 12 suitably supported as is well known in the art. As a simple manner of fastening a tile 10 on the front of the tread, I preferably utilize a clamping device which is adapted to engage the front and rear faces of the tile. Since the clamp should not prevent the tile nose or the tread surface from being exposed to traffic wear, I so form the various parts that the holding member engages the tile below the nose and preferably clamps over a projecting portion of the tile in such a manner as to keep the tile from The tile, which is here shown as a flat plate having a substantially rectangular tread surv face, may be shaped in various forms, but is preferably provided with a projecting portion adapted to cooperate with the clip to secure the tile in lace. As shown in Fig. 1, it 'is provided with a projecting portion adapted to be engaged by the clip. This may be formed, for example, by providing a shallow, longitudinal groove 16 in the front edge of the tile, although various other mechanically equivalent constructions may obviously be provided. The short arm of the metal clip 'is so shaped relative to the groove 16 as to make a tight fit therein when the tile rests firmly against the long arm of the clip.

Cooperating with the clip 13 and permitting the tile to be removed and adjustably positioned is a clamping strip 18 suitably fastened to the tread member 11 as by means of screws 19. This strip 18 engages the rear face of the tile and holds it forward against the clip and prevents the rear portion of the tile lifting from the foundation. Ihis strip 18 may be sufficiently wide to cover the entire rear portion of the stair, but I preferably form it as a narrow piece and fill in the space in the rear with suitable material. For example, I may utilize an ordinary wooden board 20 which has its upper surface in the same plane with the tiles and thus provide asmooth and continuous tread surface.

As a modification sho 'ng adifierent form of tile which may be che ply manufactured as well as easily mounted on a stair, the construction in Fig. 2 may well be utilized. In this case the tile has its front and rear faces 22 and 23 bevelled to provide clamping projections. With a tile of this shape the front clip 24 is substantially L-shaped but with its upstanding portion bent inwardly to correspond with the bevel of the tile. Similarly the fastening strip 18 has its front face bevelled to correspond with the rear of the tile, whereby the tile is absolutely prevented from being raised or loosened from its setting. In this modification the clip is shown as countersunk in the wooden base member 11. If desired, the tile shown in Fig. 1 may be provided with a rear projection similar with its front face or bevelled as shown in Fig. 2, and the clamping device will be modified accordingly.

In order to provide a resilient or cushioning support for the tiles, I preferably provide a layer of suitable material, such .as felt, asphalt paper or an asphalt mastic. In the form shown in Fig. 1, this layer 25 extends rearwardly from the clip- 13 and so provides a surface on a level with the upper face of the clip. As shown in Fig. 2, the resilient material 25 may extend across the top of the clip and thus support the whole under surface of the tile. Since the pedestrian trafiic does not ordinarily reach the extreme ends of the stair, I may fill in these outer portions with a wooden board 26, as shown in Fig. 1.

. A stair tread made in accordance with my invention is not only completely anti-slipping throughout the surfaces which bear the traffic over it, but be nichiy as memes sembled and the elements are held rigidly in position. Moreover, they may be readily removed in case of necessity and although the wear on such tiles is almost negligible, my invention provides for obtaining the utmost length of service from a given installation of tile without renewing them or spending an appreciable amount of labor in resetting. Moreover, the layer of resilient material which is used under the titles gives a slight rebound to the pressure of a step upon them which, though slight, overcomes the objection of a hard, non-yielding floor surface to walk upon.

Obviously modifications may be made of my invention and diderent materials may be employed from those which I have specified, but such applications of it are to be considered as included by the above specification and in the following claims. It is also to be understood that this invention is applicable for forming a platform edging and the like; hence the claims are to be so construed as to cover this broader field.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A stair tread comprising a tread base, a row of safety tiles on the front of the base which form the stair nose, and a clamping device secured'to the base and engaging the front edge of a tile but leavin the nose thereof exposed, said tiles providing a plane unobstructed tread surface for pedestrian use.

2. A stair tread comprising a tread base, a rear tread portion thereon, a row of safety tiles on the front of the base which form the stair nose, a; clip secured to the base and engaging the front of each tile but leaving the nose thereof exposed, and means to clamp the rear of the tile in position on the base, said parts forming a plane unobstructed tread surface.

3. A stair tread comprising a tread base, a row of safety tiles on the front of said base which form the tread nose, each tile having a safety nosing and a portion beneath the nosing projecting outwardi a clip secured to the base and clamping a ove and against said projecting portion of the tilebut leaving the nosing exposed and means in the rear of the tile to wedge the tile against said clip and secure it in position.

4. A stair tread comprising a tread base, a row of safety tiles on the front thereof, each tile having an exposed nosing and a projection therebeneath, a clip secured to the tread base having an upwardly and inward ly turned portion clamping over said projec= tion to hold the front of the tile down to its foundation and a rear tread level with the tiles including a clamping strip secured to the best nd h lding the. tiles against chn.

ill

memes 5. A stair tread comprising a tread base havin a plane rear tread surface, a row of sa ety tiles on the front of the base, a clip secured to the base and projecting upwardly into contact with the front face of the tiles, cushioning material beneath the tiles to absorb shocks and means to clamp the tiles removably against said clip and in position on the tread base, said tiles constituting the nose of the tread and providing a plane unobstructed surface for pedestrian use.

6. A stair tread comprising a base, a.

bonded abrasive tileon the base havingla r projection in the front ortion thereof, a c secured to the base an enga ing said rojection but leaving the tile e ge expos as the stair nose, a layer of cushionin material between 'said tile and the base an a wedge strip removably engaging the rear face of said tile for clamping it in place against the clip and fastening it to the base.

Signed at Worcester, Massachusetts, this 6th day of Dec. 1921.

EDWARD VAN DER PYL. 

